Loss is assigned to the past, time and time again (7)
I believe the answer is:
wastage
'loss' is the definition.
(I know that wastage is a type of loss)
'past time and time again' is the wordplay.
'past' becomes 'was' (I've seen this in another clue).
'time' becomes 't' (abbreviation).
'and' means one lot of letters go next to another.
'time again' becomes 'age' (an age is a period of time. I am not sure about the 'again' bit.).
'was'+'t'+'age'='WASTAGE'
'is assigned to the' is the link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for wastage that I've seen before include "natural decay" , "Loss (if natural, without dismissals)" , "Useless spending" , "Loss through decay" , "Loss through careless use" .)